Indigo Milk Cap Mug

Lactarius indigo, commonly known as the indigo milk cap, or the blue milk mushroom, is a species of agaric fungus in the family Russulaceae. A widely distributed species, it grows naturally in eastern North America, East Asia, and Central America. The fungus body color ranges from dark blue in fresh specimens to pale blue-gray in older ones. The milk, or latex, that oozes when the mushroom tissue is cut or broken is also indigo blue, but slowly turns green upon exposure to air.